Acrosalenia hemicidaroides and encrine (isocrinus sp.). Bajocian (168 million years). Vosges, France. The preservation of sea urchins with their quills is exceptional, since they come off as soon as the animal dies. The analysis of the outcrop shows that the stratum with the sea urchins is surmounted by a sand dune several meters thick. We can assume that a hydraulic dune quickly buried the living sea urchins, making this exceptional preservation possible.- Blouet brothers collection